Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have reported previously that the cytolytic activity of murine CD8(+) cytotoxic T lymphocytes (CTL) specific for HIV-1 gp160 envelope glycoprotein was markedly inhibited by brief exposure to the free minimal antigenic peptide (I-10: 10mer peptide from gp160) by direct binding to class I MHC molecules of specific CTL in the absence of antigen-presenting cells (APC). Here, we show that treatment of such CTL with the peptide induced not only the inhibition of cytolytic activity but also IL-2Rbeta down-modulation, followed by the inhibition of IL-2-dependent growth. The peptide-mediated inhibition and restoration of expression of IL-2Rbeta were well correlated with changes in both cytolytic activity and IL-2-dependent growth of the CTL. Since enzymatic activity of granzyme B, and mRNA expression of granzyme B and perforin were significantly reduced in peptide-treated CTL, the inhibition of cytolytic activity was mainly caused by the exhaustion of cytolytic molecules. Moreover, treatment of the CTL with the epitopic peptide resulted in production of high levels of IL-2, IFN-gamma, tumor necrosis factor-alpha and MIP-1beta in the culture supernatant. Maximum amounts of cytokines were obtained in the culture supernatant when the level of cytolytic activity was the lowest. Thus, although the CTL temporarily lost their cytolytic activities, they simultaneously gained the abilities to produce cytokines for activation of various cell populations. These changes induced by free antigenic peptide in CD8(+) CTL reveal an interesting counter-regulation between their cytolytic activities and cytokine production.
 ...
PMID:Counter-regulation of cytolytic activity and cytokine production in HIV-1-specific murine CD8+ cytotoxic T lymphocytes by free antigenic peptide. 1113 33

Lisa Capaldini, a physician who treats patients with HIV-related fatigue, discusses symptoms, diagnosis techniques, and treatments of depression, anemia, and various other roots of fatigue in HIV-positive patients. Biochemical depression, caused by abnormal levels of serotonin and norepinephrine in the brain, is easily misdiagnosed or overlooked. Physical and emotional symptoms of depression mirror common effects of HIV such as exhaustion, anger, and irritability. Knowing the history of depression prior to HIV infection, including previous drug abuse and family history of depression, will help to diagnose fatigue. Dr. Capaldini recommends antidepressants provided the condition is properly diagnosed and the side effects are not harmful to the patient. Selective serotonin reuptake inhibitors (SSRI), the most frequently prescribed antidepressants, can cause short term sexual dysfunction. Bupropion and Wellbutrin can be prescribed to avoid this side effect. Psychotherapy can be effective if therapists are familiar with HIV disease and can distinguish between symptoms brought on by behavior, addictive habits, or pre-existing depression. Consideration also must be given to drug interactions, particularly with the antiretrovirals ritonavir and delavirdine, which can cause seizures or disturb cardiac rhythm. Anemia is most noticeable after physical exertion, and symptoms are more evident based on the increased rate that red blood cells move out of the normal range. To determine the course of treatment, physicians need to clarify the cause of anemia. Anemia can be caused by drugs, vitamin deficiencies, or other nutritional problems. Adrenal insufficiency, methemoglobinemia, and malnutrition are also causes of fatigue. Diagnosing fatigue due to hepatitis B or C, rather than HIV, can be achieved by measuring hepatitis levels and observing T cell counts and viral load. Dr. Capaldini suggests that proper diet and exercise prevent fatigue from getting worse.
 ...
PMID:Fatigue and HIV: interview with Lisa Capaldini, M.D. Part II. Interview by John S. James. 1136 84

The article addresses the importance of psychotherapy for HIV-infected gay men in managing their illness. An historical overview and current perspective of the psychosocial issues related to HIV, and presented in psychotherapy, is given. Silent issues related to treatment adherence and unsafe sexual practices are also reviewed. Psychotherapy can be used to change current behaviors, most notably to decrease the incidences of unprotected sex and medication adherence. Psychotherapists should consider the subtler and pervasive effects of HIV, its impact on adult maturation, and the emotional exhaustion of many HIV-infected gay men.
 ...
PMID:Current therapy issues for gay men with HIV. 1136 34

Fatigue, a common presenting complaint in primary care, is described as a lack of energy, sleepiness, tiredness, exhaustion, an inability to get enough rest, or weakness. Thus, fatigue affects quality of life. The prevalence rate of fatigue among patients with HIV infection is estimated to be 20% to 60%, and as the disease worsens, fatigue may become even more prevalent. The causes of HIV-related fatigue may be multifactorial and may include lack of rest or exercise, or improper or inadequate diet; psychological stress including depression and anxiety; the use of recreational substances; anemia; abnormalities of the thyroid gland and hypogonadism; infections; side effects of medications; sleep disturbances; and fever. This article reviews the common causes of HIV-related fatigue and briefly discusses options for reducing fatigue.
 ...
PMID:Assessment and treatment of HIV-related fatigue. 1156 35

To assess stress and satisfaction related to HIV medical work and its impact on psychological wellbeing, a cross-sectional study was undertaken among the population of doctors caring for HIV/AIDS patients in French hospitals. They were sent a questionnaire on demographic and professional characteristics along with three additional scales: the Consultants Mental Health Questionnaire with three components - stress, satisfaction and responses to job stress; the Maslach Burnout Inventory; and the GHQ-12 (General Health Questionnaire). A total of 670 physicians responded anonymously (65.4% participation). For 45% of respondents, HIV/AIDS represented less than 25% of their activity. Three dimensions were extracted by multivariate analysis from the stress scale (overload, social relationships at work, patients/family distress) and four dimensions from the satisfaction scale (work content, patients/family, peer recognition, work environment). Length of time working in HIV/AIDS, and proportion of clinical work in HIV/AIDS were not related to either stress or satisfaction. Only participation in NGOs increased the level of stress. Stress was not related to time spent in clinical work, neither to HIV work. Satisfaction derived from work decreases with time in direct contact with patients and is mainly related to the position in hospital. Eleven per cent sought help from professionals for psychological problems. Stress derived from patients suffering was not related to any psychological outcomes. Work overload and stress derived from social relationships at work are the main predictors of psychological distress, emotional exhaustion and depersonalization, while the moderator effect of satisfaction is weak. In the late nineties, the amount of HIV work did not appear as a specific feature of hospital medical work.
 ...
PMID:Psychological stress among hospital doctors caring for HIV patients in the late nineties. 1172 Jun 46

Current recommendations indicate the use of HIV-1 drug resistance genotyping in the treatment of HIV-1 infection, primarily on treatment failure, and in specific instances also before the initiation of therapy. As such, HIV-1 genotyping is becoming a standard of care parameter in HIV-1 treatment monitoring and a rapidly increasing number of laboratories now use this technology routinely. A study of proficiency, using the ENVA-2 panel, was performed to evaluate the current HIV-1 resistance genotyping quality in 34 laboratories from different parts of the world. The results demonstrated extensive interlaboratory variation in the quality of genotyping and a significant underestimation of resistance mutations, even in samples expressing pure mutant genotype. The level of variation could not be attributed to the sequencing technology used and was therefore considered to be laboratory associated. The direct clinical consequences of this may be inadequate treatment of HIV-1-infected individuals and a more rapid exhaustion of therapeutic options for the patients. Drug resistance mutations are frequently missed. Therefore, quality control programs are urgently needed. Until these are widely implemented, clinicians must consider this issue and interpret the reported genotyping results with caution.
 ...
PMID:Underestimation of HIV type 1 drug resistance mutations: results from the ENVA-2 genotyping proficiency program. 1186 Jun 70

April 27, 1994, marked the end of the apartheid era in South Africa, but still the infant mortality rate is 130/1000 live births for Blacks compared to 13/1000 for Whites. Diarrhea, acute respiratory infections, malnutrition, and measles account for an estimated ninefold excess of deaths among Black children under 5 years old relative to their White counterparts. In Cape Town the under-five-years mortality rate for the mixed Colored population is 20.5/1000 compared to 4.6/1000 for Whites. In 1992, 19,000 measles cases were recorded. Diarrhea accounts for 20% of the deaths in the under-five group. In Cape Town alone, intestinal infections accounted for 27% of deaths in children followed by acute respiratory infections at 16%, and nutritional deficiencies at 10%. About 100,000 new cases of tuberculosis occur annually. There are currently 350,000 to 400,000 HIV-infected people in South Africa, and the mounting numbers pose a major threat to the health services. The fragmented public health system of South Africa is undergoing rationalization. The new government has extended universal public health care to children under 6 years old and to pregnant mothers. This reform, however, has resulted in undue strain on health services because of financial and staff constraints. Many doctors are threatening to leave the public service because of the increased workload without a concomitant increase in medical or paramedical staffing. Numerous clinics are reporting complete exhaustion of supplies of essential drugs. Currently only 5% of the health care budget is being spent on primary health care and only 3.6% of the public sector GDP is spent on health care. Political commitment, upgrading of skills in public health, redefinition of the government's role, emphasis on education, communication, public-health legislation, direct involvement in health care and research, and greater participation in health issues are required.
 ...
PMID:Child health in South Africa -- past, present and future. 1234 56

That HIV-specific cytotoxic T-lymphocytes (CTLs) might be defective in some way has stimulated much controversy and research. We use mathematical models to explore the predictions of two competing CTL-defect theories: "defective memory" and "defective activation". We discuss whether these models are consistent with adoptive-transfer experiments in HIV-infected patients and vaccine trials in simian immunodeficiency virus (SIV)-infected monkeys. Finally, we describe experimental tests that could decide among these two theories and a competitor: CTL exhaustion.
 ...
PMID:What's the matter with HIV-directed killer T cells? 1239 72

HIV infection leads to reduced numbers and increased turnover of CD4(+) T cells in blood. However, blood represents only 2% of the total lymphocyte pool, and information about other organs is lacking, leading to controversy about the effects of HIV infection on T-cell homeostasis. Therefore, we have determined phenotype and turnover of lymphocyte subsets in various tissues of macaques. Infection with simian immunodeficiency virus (SIV) resulted in increased proliferation rates of T cells in all organs. Despite reduced CD4 counts in blood, absolute numbers of CD4(+) T cells were increased in spleen and lymph nodes and remained stable in nonlymphoid organs such as liver, lung, bone marrow, and brain during the asymptomatic phase, indicative for an altered tissue distribution. In animals killed with first signs of AIDS, total body CD4 counts and proliferation rates had returned to control levels, whereas thymocytes were almost completely absent. Our data show that a drastically increased turnover in the early stages of HIV infection, driven by a generalized immune activation rather than a homeostatic response to CD4(+) T-cell destruction, is followed by exhaustion of the regenerative capacity of the immune system.
 ...
PMID:Impact of simian immunodeficiency virus (SIV) infection on lymphocyte numbers and T-cell turnover in different organs of rhesus monkeys. 1239 72

During primary viral infection, in vivo exposure to high doses of virus causes a loss of Ag-specific CD8(+) T cells. This phenomenon, termed clonal exhaustion, and other mechanisms by which CTLs are deleted are poorly understood. Here we show evidence for a novel form of cell death in which recently stimulated CD8(+) HIV-1 envelope gp160-specific murine CTLs become apoptotic in vitro after brief exposure to free antigenic peptide (P18-I10). Peak apoptosis occurred within 3 h of treatment with peptide, and the level of apoptosis was dependent on both the time after initial stimulation with target cells and the number of targets. Using T cell-specific H-2D(d)/P18-I10 tetramers, we observed that the apoptosis was induced by such complexes. Induction of apoptosis was blocked by cyclosporin A, a caspase 3 inhibitor, and a mitogen-activated protein kinase inhibitor, but not by Abs to either Fas ligand or to TNF-alpha. Thus, these observations suggest the existence of a Fas- or TNF-alpha-independent pathway initiated by TCR signaling that is involved in the rapid induction of CTL apoptosis. Such a pathway may prove important in the mechanism by which virus-specific CTLs are deleted in the presence of high viral burdens.
 ...
PMID:Rapid induction of apoptosis in CD8+ HIV-1 envelope-specific murine CTLs by short exposure to antigenic peptide. 1244 71


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>